Our ability to answer questions about the past is shaped by the available sources. In some cases, the challenge is to sift through a vast amount of information to find the evidence that matters most. Starting with the print revolution of the fifteenth and sixteenth centuries, for example, the production of documents by Europeans exploded; thus a historian studying nineteenth-century England confronts a mountain of newspapers, legal documents, business records, books, letters, and diaries. The historian studying ancient Egypt, in contrast, is presented with very different difficulties: namely, the paucity of sources and the role of chance in the survival and discovery of evidence. The Egyptian historian is even at a disadvantage relative to a colleague who studies Mesopotamia, since Mesopotamian clay tablets proved much more durable than Egyptian papyrus. Thus Egyptian history is replete with unsolved mysteries. What motivated Thutmose III’s effort to erase the reign of Hatshepsut some twenty years after her death? We know that her images were defaced, destroyed, and altered, but, barring the discovery of new evidence, we may never know why. Consider these issues as you listen to a short audio lecture on Herbert Winlock’s excavations at Deir el-Bahri, produced by New York’s Metropolitan Museum of Art.